000
AGXX40 KNHC 031903
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
303 PM EDT SAT AUG 3 2013

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN
SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND
64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS.

...GULF OF MEXICO MODEL PREFERENCE: HIGH CONFIDENCE. LATEST
GFS/ECMWF BLENDED WITH OFFICIAL FORECAST. NWPS USED FOR WAVE
PARAMETERS.

THE NORTHERN PORTION OF A WEAK TROPICAL WAVE WAS ANALYZED OVER
THE WESTERN BAY OF CAMPECHE THIS MORNING. A FEW SHOWERS WERE NOTED
WITH THIS FEATURE EARLIER BUT HAVE SINCE DISSIPATED. FARTHER TO
THE EAST...AN UPPER LOW OVER THE NW CARIBBEAN ENHANCED MODERATE
CONVECTION OVER THE COASTAL PORTIONS OF THE YUCATAN PENINSULA THIS
MORNING. ELSEWHERE...THE MAIN WEATHER INFLUENCE CONTINUES TO BE A
RIDGE EXTENDING EAST TO WEST ALONG ROUGHLY 27N.
BUOY...SHIP...ALTIMETER...AND SCATTEROMETER DATA INDICATE
GENERALLY LIGHT WINDS AND MODEST SEAS ACROSS THE GULF. THE RIDGE
AXIS WILL SHIFT S SLIGHTLY THROUGH SUN...AHEAD OF A COLD FRONT
MIGRATING S ACROSS THE DEEP SOUTH STATES. THE FRONT WILL STALL N
OF THE GULF THROUGH THE EARLY PORTION OF NEXT WEEK...AND BECOME
DIFFUSE THROUGH MID WEEK. WINDS WILL REMAIN FAIRLY LIGHT...WITH
THE EXCEPTION OF MODERATE TO FRESH SE RETURN FLOW OVER THE FAR NW
GULF BY MID WEEK AHEAD OF A WEAK TROUGH MOVING THROUGH THE CENTRAL
PLAINS. IN ADDITION...EXPECT THE NORMAL OVERNIGHT. 20 KT FLOW OUT
OF THE NE ALONG THE WEST COAST OF YUCATAN EACH NIGHT. NO
SIGNIFICANT DIFFERENCES IN MODEL OUTPUT.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC...                    
MODEL PREFERENCE: HIGH CONFIDENCE. LATEST GFS/ECMWF BLENDED
WITH OFFICIAL FORECAST. NWPS USED FOR WAVE HEIGHTS EXCEPT WNA USED
FOR S CENTRAL CARIBBEAN SECTOR.

RIDGING OVER THE N CENTRAL ATLC WILL MAINTAIN FRESH TO STRONG
WINDS OVER THE S CENTRAL CARIBBEAN...WITH NEAR 30 KT OFF COLOMBIA
PARTICULARLY DURING THE OVERNIGHT AND EARLY MORNING HOURS. A
MORNING ALTIMETER PASS INDICATED SEAS APPROACHING 12 FT OFF
COLOMBIA WHICH IS PLAUSIBLE GIVEN THE FETCH AND DURATION OF THE
STRONGER WINDS. GENERALLY MODERATE FLOW PERSISTS ELSEWHERE WITH
SEAS 3 TO 5 FT. THE PATTERN WILL GRADUALLY TRANSITION THROUGH MID
WEEK AS A TROUGH/TROPICAL WAVE APPROACHES FROM THE TROPICAL
EASTERN ATLC. THIS WILL COINCIDE WITH THE PUSH OF A MID LATITUDE
TROUGH THROUGH U.S. EAST COAST INTO THE WESTERN ATLC.
TOGETHER...THESE FEATURES WILL SERVE TO WEAKEN THE ATLC RIDGE AND
THUS ALLOW WINDS AND SEAS TO DIMINISH ACROSS THE CARIBBEAN BASIN
AND THE TROPICAL ATLC WATERS W OF 55W.

...SW N ATLANTIC W OF 55W INCLUDING THE BAHAMAS...
MODEL PREFERENCE: HIGH CONFIDENCE. TCMAT4 RUN WITH LATEST
GFS/ECMWF BLENDED WITH OFFICIAL FORECAST. WW3 USED FOR WAVE
PARAMETERS (NWPS NOT AVAILABLE).

TROPICAL DEPRESSION DORIAN NEAR 30.6N 78.4W 1013 MB AT 11 AM EDT
MOVING NE AT 12 KT. MAXIMUM SUSTAINED WINDS 30 KT GUSTS 40 KT.
DORIAN WILL MOVE N OF THE AREA TO 32.1N 77.2W THIS EVENING...THEN
TO 34.0N 73.5W BY EARLY SUN WITH MAXIMUM WINDS TO 25 KT. NO
WARNINGS ARE IN EFFECT.

OTHERWISE...1029 MB HIGH PRES CENTERED IN THE N CENTRAL ATLC NEAR
35N29W WITH A RIDGE EXTENDING TO THE W ALONG 30N/29N. LIGHT SE-S
WINDS ARE IN THE NE CORNER OF THE BASIN CLOSEST TO THE HIGH...WITH
MODERATE TO LOCALLY FRESH ANTICYCLONIC WINDS ELSEWHERE. THIS ATLC
RIDGE WILL PREVAIL INTO EARLY NEXT WEEK...MAINTAINING GENERALLY
LIGHT TO MODERATE FLOW N OF 22N. THE RIDGE WILL SHIFT S TO 26N
EARLY NEXT WEEK...AHEAD OF A SECOND FRONTAL TROUGH BOUNDARY
APPROACHING THE AREA. THE FRONTAL TROUGH IS FORECAST TO BREACH S
OF 31N MON...STALLING FROM NEAR BERMUDA TO 28N80W BY TUE MORNING
...GRADUALLY DISSIPATING THROUGH WED. S OF 22N...MODERATE TO FRESH
EASTERLY WINDS WILL PREVAIL IN THE TIGHTER GRADIENT S OF THE RIDGE.
THESE ENHANCED TRADES WILL PERSIST ACROSS THE SAME WATERS THROUGH
THE MIDDLE OF NEXT WEEK. AN TROPICAL WAVE WILL MIGRATE W ACROSS
THE WATERS S OF 22N THROUGH THE MIDDLE OF NEXT WEEK.

$$

.WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE
COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE:

.GULF OF MEXICO...
GMZ011...NONE.
GMZ013...NONE.
GMZ015...NONE.
GMZ017...NONE.
GMZ019...NONE.
GMZ021...NONE.
GMZ023...NONE.
GMZ025...NONE.

.CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
AMZ011...NONE.
AMZ013...NONE.
AMZ015...NONE.
AMZ017...NONE.
AMZ019...NONE.
AMZ021...NONE.
AMZ023...NONE.
AMZ025...NONE.
AMZ027...NONE.
AMZ029...NONE.
AMZ031...NONE.
AMZ033...NONE.
AMZ035...NONE.
AMZ037...NONE.
AMZ039...NONE.

.SW N ATLANTIC INCLUDING THE BAHAMAS...
AMZ111...NONE.
AMZ113...NONE.
AMZ115...NONE.
AMZ117...NONE.
AMZ119...NONE.
AMZ121...NONE.
AMZ123...NONE.
AMZ125...NONE.
AMZ127...NONE.

*FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT:
HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF

NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE
NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT:
HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP

FOR ADDITIONAL INFORMATION PLEASE VISIT:
HTTP://WWW.HURRICANES.GOV/MARINE

$$
.FORECASTER CHRISTENSEN. NATIONAL HURRICANE CENTER.